Mechanical hand having computer-type drive mechanisms for producing numerous hand articulations similar to a human hand



O 1967 J. A. GENTILUOMO MECHANICAL HAND HAVING COMPUTER-TYPE DRIVE MECHANISMS FOR PRODUCING NUMEROUS HAND AR TICULATIONS SIMILAR TO A HUMAN HAND 3 Sheets-Sheet 1 Filed 00?. '7 1963 mwm Em :N 2 m ll-ll mmm N m mm m ON INVENTOR. JOSEPH A, GENTIILUOMO BY M Oct. 10, 1967' J. A. GENTILUOMO 3,

MECHANICAL HAND HAVING COMPUTER-TYPE DRIVE MECHANISMS FOR PRODUCING NUMEROUS HAND ARTICULATIONS SIMILAR TO A HUMAN HAND 5 Sheets-Sheet 2 Filed Oct.

n u w-. 3 mmw vim m l l M rl u E 3. ac m2 1 mm mmm Sm INVENTOR. JOSEPH A. G ENTIELUOMO M m Oct 10, 1967 J. A. GENTILUOMO 3,345,647

MECHANICAL HAND HAVING COMPUTER-TYPE DRIVE MECHANISMS FOR PRODUCING NUMEROUS HAND ARTICULATIONS SIMILAR TO A HUMAN HAND Filed 001;. 7, 1963 5 Sheets-Sheet 5 FIG.5.

BYM a United States Patent Gflfice MECHANICAL HAND HAVING COMPUTER-TYPE DRIVE MECHANISMS FOR PRGDUCING NU- MEROUS HAND ARTICULATIONS SIMILAR TO A HUMAN HAND Joseph A. Gentiluomo, 1456 Belmont Ave., Schenectady, N.Y. 12308 Filed Oct. 7, 1963, Ser. No. 314,148 6 Claims. (Cl. 312.7)

This invention relates to a mechanical hand for use in solving the problems either of hand prosthesis or remote handling depending upon which application of this invention is desired.

The problems of hand prosthesis and remote handling are the need for a mechanical hand that upon actuation will function as a human hand functions. In this connection it should be discerned and appreciated that the anatomy of the human hand comprises the carpus and meta carpus which include the first metacarpal associated with the first phalanx and second phalanx of the thumb, the second metacarpal associated with the proximal phalanx, middle phalanx and the distal phalanx of the forefinger, the third metacarpal associated with the proximal phalanx, middle phalanx and distal phalanx of the middle finger, the fourth metacarpal associated with the proximal phalanx, middle phalanx and distal phalanx of the ring finger, and the fifth metacarpal associated with the proximal phalanx, middle phalanx and distal phalanx of the little finger.

Human hand motions or articulations comprise thumb pivot, thumb curl, finger pivot, finger curl and wrist pivot. These human hand motions or articulations can be effected separate and distinct from one another or in combination with one another contemporaneously.

Thumb pivot comprises either thumb metacarpal pivot or thumb first phalanx pivot. Thumb metacarpal pivot entails the pivoting of the first metacarpal relative to the carpus. Thumb first phalanx pivot entails pivoting of the first phalanx relative to the first metacarpal.

Thumb curl entails pivoting of the second phalanx relative to the first phalanx.

Finger pivot with respect to the forefinger, middle finger, ring finger or little finger entails the pivoting of the proximal phalanx relative to its respective metacarpal.

Finger curl entails the pivoting of both the middle and distal phalanx relative to the proximal phalanx.

Wrist pivot entails pivoting of the metacarpus relative to the carpus.

Accordingly, the objects of this invention are:

To provide a mechanical hand which simulates the human hand as nearly as possible both in appearance and in operation.

To provide a mechanical hand of such novel design as to make possible a hand of human like proportions.

To provide a mechanical hand which can be articulated to provide finger and thumb motions separate and distinct from one another or in various combinations with one another.

To provide in a mechanical hand, a novel and relatively simple finger and thumb construction which renders the fingers and thumb easily operable and capable of grasping diverse objects with substantial strength if needed.

To provide a mechanical hand which can be used for the purpose of remote handling.

To provide a mechanical hand which can be used for hand prosthesis.

To provide a mechanical hand which can be used in a master-slave manipulator.

To provide a mechanical hand which can be articulated by thought control, programed control, etc.

3,345,647 Patented Oct. 10, 1967 These objects and other objects of the invention should be discerned and appreciated from the detailed specification taken in conjunction with the drawings, wherein like reference numerals refer to similar parts throughout the several views, in which:

FIG. 1 is a top plan view, partly in section, of the invention;

FIG. 2 is a view of a finger and metacarpal partly in section, taken along the line 2-2 of FIG. 1;

FIG. 3 is a top plan view, partly in section, of the thumb of FIG. 1;

FIG. 4 is a sectional view taken along the line 4-4 of FIG. 6;

FIG. 5 is a view taken along the line 5-5 of FIG. 3;

FIG. 6 is a fragmentary view, partly in section, of the thumb shown in FIG. 3;

FIG. 7 is a View taken along the line 77 of FIG. 6.

In FIG. 1 of the drawings, reference numeral 1 generally refers to the invention. Shown freely mounted on shaft 3 by wrist frame 5 are the input spur gears 7, 9, 11, 13, 15, 17, 19, 21, 23, 25 and 27. Mounted between these input spur gears are the spacer washers 29, 31, 33, 35, 37, 39, 41, 43, 45 and 47, as shown. The input spur gears, 7, 11, 19 and 23 are operatively associated with discrete mechanical actuators for effecting finger curl of the little finger, ring finger, middle finger and forefinger, respectively. The input spur gears 9, 13, 17 and 21 are operatively associated with discrete mechanical actuators for effecting finger pivot of the little finger, ring finger, middle finger and forefinger, respectively. The input spur gear 15 is operatively associated with the device for effecting wrist pivot. Input spur gear 25 is operatively associated with the device for effecting thumb curl and input spur gear 27 is operatively associated with a discrete mechanical actuator for effecting thumb first phalanx pivot. Input spur gear 49, shown in FIG. 3, is operatively associated with a discrete mechanical actuator for effecting thumb metacarpal pivot.

As an example, the use of this invention in hand prosthesis can be achieved by the utilization of thought control in which discrete nerve impulses leading to the hand can be converted into muscle bio-currents. These biocurrents are amplified electronically by controllers which in turn function to drive the input gears which are operatively connected to their respective discrete controllers. Authority is based upon the article entitled Forearm Prosthesis Developed Utilizing Nerve Impulse Power, Medical Tribune, volume 4, Number 22, March 18, 1963.

An example of the prior art that can be utilized in remote handling to drive the input spur gears would be a servo system, whereby controllers function to provide discrete hand articulations or movements.

Finger pivot and finger curl will be described with reference to the ring finger whereof the structure is shown. It should be discerned and appreciated that the structure for effecting finger pivot and finger curl for the little finger, middle finger and forefinger would be the same.

Input spur gear 13 meshes with spur gear 51 freely mounted on wrist pivot shaft 53 fixed to the metacarpal frame structure 55. Spur gear 51 is operatively engaged with the teeth 57 of rack 59. Spur gear 61 is freely mounted on shaft 63 that is mounted in journal slot 65 of ear 67 of frame structure 55. Spur gear 61 is operatively engaged with the teeth 69 of rack 59. Rack 59 is held in its operative engagement by rack guide pins 71 and 73 carried by frame structure 55. Carried by shaft 63 is a rack 75 having its teeth 77 operatively engaged by spur gear 79 freely mounted on shaft 81.

Drive is transmitted from input spur gear 11 to spur gear 83 by a similar arrangement and disposition of another spur gear 51 and rack 59. Spur gear 83 is freely mounted on shaft 85 that is mounted in journal slot 87 a of ear 89 of frame structure 55. Carried by shaft is a rack 91 having its teeth 93 operatively engaged by spur gear 95 freely mounted on shaft 81.

Racks 75 and 91 are held in their operative engagements by respective rack guide pins 99 and 101 carried by metacarpal frame structure 55. Shaft 81 is fixed to the metacarpal frame structure 55 which also fixedly carries shaft 103 which is also the point of proximal phalanx pivot. In mesh with spur gear 79 is the sector gear portion 105 of the proximal phalanx link 107 which carries a shaft 109, a shaft 111 in its slot journal mount 113 and a shaft 115 which is also the point of the middle phalanx pivot.

In mesh with spur gear 95 is the spur gear 117 freely mounted on shaft 103 and in mesh with spur gear 119 freely mounted on shaft 109. The sector gear portion 121, as shown, of the metacarpal frame structure 55 is in mesh with spur gear 123 freely mounted on shaft 109. Spur gear 123 is operatively engaged with the teeth of rack 125 and spur gear 127 fixedly mounted on shaft 111 is operatively engaged with the teeth of rack 125. Spur gear 119 is operatively engaged with the teeth of rack 129 and spur gear 131 fixedly mounted on shaft 111 is operatively engaged with the teeth of rack 129. Racks 125 and 129 are held in their operative engagements by rack guide pins 133 and 135 carried by the proximal phalanx link 107.

Carried on shaft 111 is a rack 137 having its teeth operatively engaged by spur gear 139 fixedly mounted on shaft 115. Fixed to shaft 115 is the middle phalanx link 141 which carries shafts 143 and 145. Rack 137 is held in its operative engagement by rack guide pin 147 carried by proximal phalanx link 107. The sector gear portion 149 of proximal phalanx link 107 meshes with sector gear 151 freely mounted on shaft 143. The distal phalanx 153 is freely mounted on shaft which is the point of the distal phalanx pivot. Connecting link 155 is pivotally connected to sector gear 151 by pivot pin 157 and to the distal phalanx 153 by pivot pin 159.

Finger curl is etfectuated when input spur gear 11 transmits drive to spur gear 95 through the drive train of spur gear 51, rack 59, spur gear 83 and rack 91. Since input spur gear 13 is not transmitting any drive to spur gear 79, spur gear 79 will not rotate. Drive transmitted from input spur gear 11 to spur gear 95 will be transmitted to spur gears 117 and 119 and effect translatory movement of rack 129. Rack 129 will transmit drive to spur gears 131 and 127 fixedly mounted on shaft 111. With spur gear 79 stationary and hence without drive being transmitted to it and without it transmitting drive, proximal phalanx link 107 will remain stationary as will spur gear 123 and rack 125. Upon drive being transmitted to spur gears 131 and 127, spur gear 127 will travel along stationary rack 125 and effect translatory movement of shaft 111 within the slot journal mount 113. Such movement of shaft 111 will effect translation of rack 137 and thereby provide transmission to spur gear 139. Since spur gear 139 and middle phalanx link 141 are both fixed to shaft 115, the middle phalanx link 141 will pivot around the middle phalanx pivot point of shaft 115. Sector gear 151 will walk around the sector gear portion 149 of the stationary proximal phalanx link 107 to effect translation of connecting link 155 and pivotal movement of the distal phalanx 153.

Finger pivot is effectuated when input spur gear 13 transmits drive to spur gear 79 through the drive train of spur gear 51, rack 59, spur gear 61 and rack 75. Since input spur gear 11 is not transmitting any drive to spur gear 95, spur gear 95 will not rotate. Drive transmitted from input spur gear 13 to spur gear 79 will in turn drive the sector gear portion 105 of proximal phalanx link 107 to effect the pivoting of proximal phalanx link 107 about the proximal phalanx pivot of shaft 103. With engaged spur gears 95 and 117 stationary and hence without drive being transmitted to them and without their transmitting drive, spur gear 119 will walk around spur gear 117 effecting translatory movement of rack 129. At the same time, an opposite and equal translatory movement of rack 125 will be effected thereby preventing any movement of shaft 111 in its slot journal mount 113. Rack 125 translates upon spur gear 123 which walks around the sector gear portion 121 of the metacarpal frame structure 55.

When input spur gears 11 and 13 simultaneously transmit drive through their respective drive trains to their respective spur gears 95 and 7 9, combined finger curl and finger pivot will be effectuated as each was described previously.

In order to provide drive from the input gears to the forefinger and middle finger an offset gear arrangement of intermediate gears is utilized.

The middle finger is intermediately connected by the use of gears 355 and 357 which are fixed to shaft 359 and gears 361 and 363 which are integral and free to rotate on shaft 359.

In operation rack 365 transmits drive through gears 355 and 357 to incite finger pivot of the middle finger. Rack 367 transmits drive through gears 361 and 363 to incite finger curl to the middle finger.

The forefinger is intermediately connected by the use of gear 369 and 371 which are fixed to shaft 373, gears 375 and 377 which are integral and free to rotate on shaft 373, and gears 37 9 and 381 which are free to rotate on shaft 383.

In operation rack 385 transmits drive through gears 369, 371, 381 to incite finger pivot of the forefinger. Rack 387 transmits drive through gears 375, 377 and 379 to incite finger curl to the forefinger.

Input spur gear 49 is fixedly mounted on shaft 161 freely mounted on ear 163 of wrist frame 5. Input spur gear 49 meshes with the sector gear teeth 165 of sector gear 167 mounted on shaft 169 carried by wrist frame 5. Freely mounted on shaft 169 is a spur gear 171 which meshes with spur gear 173 fixedly mounted on shaft 175 carried by sector gear 167. Spur gear 177 fixedly mounted on shaft 175 meshes with spur gear 179 freely mounted on shaft 180 carried by sector gear 167.

Spur gear 171 is operatively engaged with the teeth of rack 181. Spur gear 183, operatively engaged with the teeth of rack 181, is fixed to a bevel gear 185, and both spur gear 183 and bevel gear 185 are freely mounted on the wrist pivot shaft 53 that is fixed to metacarpal frame structure 55 and freely mounted in the wrist frame 5. Rack 181 is held into operative engagement with spur gears 171 and 183 by rack guide pins 187 and 189 carried by support structure 191 of wrist frame 5.

Fixed to wrist pivot shaft 53 is a block 193 having a shaft 195 freely journalled therethrough. Spur gear 197, fixed to wrist pivot shaft 53, meshes with spur gear 199 freely mounted on shaft 169. Spur gear 199 meshes with spur gear 179. Interposed between block 193 and spur gear 197 is a bevel sector gear 196 freely mounted on wrist pivot shaft 53 and fixed to wrist frame 5, as shown. Fixed to shaft 195 is a bevel gear 198 in mesh with bevel sector gear 196. The first metacarpal link 201 is pivotally mounted on shaft 195 which is the point of the first metacarpal pivot. First metacarpal link 201 has a bevel sector gear portion 203 in mesh with bevel gear 185.

In mesh with input spur gear 25 is spur gear 205 fixed to bevel sector gear 207. Both spur gear 205 and bevel sector gear 207 are freely mounted on wrist pivot shaft 53. In mesh with input spur gear 27 is spur gear 209 fixed to bevel sector gear 211. Both spur gear 209 and bevel sector gear 211 are freely mounted on wrist pivot shaft 53. Spur gear 213 is fixedly mounted on shaft 195. Spur gear 215 and bevel gear 217 are fixed to each other and both are freely mounted on shaft 195. Bevel gear 217 meshes with bevel sector gear 207. Spur gear 219 is fixedly mounted on shaft 195. Spur gear 221 and bevel gear 223 are fixed to each other and both are freely mounted on shaft 195.

Spur gear 225 is fixedly mounted on translating shaft 227. Spur gear 213 and spur gear 225 are operatively engaged with the teeth of rack 229. Spur gear 215 and spur gear 225 are operatively engaged with the teeth of offset rack 231. Spur gear 233 is fixedly mounted on translating shaft 235. Spur gear 219 and spur gear 233 are operatively engaged with the teeth of offset rack 237. Spur gear 221 and spur gear 233 are operatively engaged with the teeth of rack 239. Rack guide pins 241 and 243 carried by the auxiliary first metacarpal link 245 hold racks 229 and 231 in their operative engagements, respectively. Rack guide pins (not shown), carried by the first metacarpal link 201 holds racks 237 and 239 in their operative engagements.

Shaft 247 is fixed to first metacarpal link 201 and auxiliary first metacarpal link 245. Spur gears 249 and 251 are freely mounted on shaft 247. Spur gear 249 is operatively engaged with the teeth of rack 253 freely mount ed on shaft 227. Spur gear 251 is operatively engaged with the teeth of rack 255 freely mounted on shaft 235. Rack guide pin 257 carried by the auxiliary first metacarpal link 245 holds rack 253 in its operative engagement. A rack guide pin (not shown) carried by the first metacarpal link 201 holds rack 255 in its operative engagement.

The first phalanx link 259 is pivotally mounted on shaft 261 which is the point of the first phalanx pivot. Shaft 261 is freely mounted with respect to the first metacarpal link 201 and the auxiliary first metacarpal link 245. Spur gear 263, fixedly mounted on shaft 261, is in mesh with spur gear 249. Spur gear 265 is freely mounted on shaft 261. Spur gear 265 is fixed to first metacarpal link 201. The sector gear portion 267 of the first phalanx link 259 meshes with spur gear 251. Spur gears 269 and 271 are fixedly mounted on shaft 273 freely carried in the slot journal mount 275 of first phalanx link 259. Spur gear 263 and spur gear 269 are operatively engaged with the teeth of rack 277. Spur gear 265 and spur gear 271 are operatively engaged with the teeth of rack 279. Rack guide pin 281 carried by the first phalanx link 259 holds rack 277 in its operative engagement. A rack guide pin 283 carried by the first phalanx link 259 holds rack 279 in its operative engagement.

Shaft 285 is freely carried by the first phalanx link 259 and is the point of the second phalanx pivot. Spur gear 287 and the second phalanx 289 are fixed to shaft 285. Spur gear 287 is operatively engaged with the teeth of rack 291 freely carried by shaft 273. Rack guide pin 293 holds rack 291 in its operative engagement.

Thumb metacarpal pivot is eifectuated when input spur gear49 transmits drive to spur gear 183 through the drive train of sector gear 167 with spur gears 177, 179,

and 199, spur gears 173 and 171, and rack 181. Since spur gear 183 is fixed to bevel gear 135, the drive from input spur gear 49 is transmitted to the bevel sector gear portion 203 meshing with bevel gear 185. Hence the first metacarpal link 201 will thereby pivot about shaft 195. Racks 229, 231, 237 and 239 translate driving spur gears 225 and 233, respectively. The translatory movement of racks 229, 231, 237 and 239 will be relative to the driven first metacarpal link 201 such that racks 253 and 255 do not translate. Since racks 253 and 255 do not translate there is no drive transmitted to the first phalanx link 259 and second phalanx 289.

Thumb first phalanx pivot is effectuated when input spur gear 27 transmits drive to spur gear 209. Since spur gear 209 is fixed to bevel sector gear 211, bevel gear 223 fixed to spur gear 221 .is driven by bevel sector gear 211. In turn, driven spur gear 221 will effect translatory movement of rack 239 transmitting drive to spur gear 233 fixed to translating shaft 235. Spur gear 233 walks along offset rack 237, which is stationary, with resulting translatory movement of rack 255. Rack 255 transmits drive to spur gear 251 which meshes with the sector gear portion 267 of first phalanx link 259. The

' first phalanx link 259 thereby pivots about shaft 261.

From the previous description of thumb metacarpal pivot,

itshould be appreciated that with no input to input spur gear 49 the first metacarpal link 201 will remain stationary. With no input drive transmitted to input spur gear 25, no thumb second phalanx pivot or thumb curl will be eifectuated. This arises out of the fact that spur gear 263 will not be driven. As the first phalanx link 259 pivots about shaft 261 racks 277 and 279 will translate in opposite directions and thereby spur gears 269 and 271 will rotate about common shaft 273 but will not translate. And with no movement of common shaft 273, rack 291 will not translate to cause second phalanx pivot.

Thumb second phalanx pivot or thumb curl is effect-uated when input spur gear 25 transmits drive to spur gear 205. Since spur gear 205 is fixed to bevel sector gear 207, bevel gear 217 fixed to spur gear 215 is driven by bevel sector gear 207. With no input drive to either of input spur gears 27 and 49 to effect thumb metacarpal pivot and thumb first phalanx pivot, respectively, spur gear 213 fixed to shaft will remain stationary as will rack 229. Driven spur gear 215 will effect translation of offset rack 231 thereby transmitting drive to spur gear 225 fixed to translating shaft 227. Spur gear 225 walks along rack 229, which is stationary, with resulting translatory movement of rack 253. Rack 253 transmits drive to spur gear 249 in mesh with spur gear 263 fixed to shaft 261. Driven spur gear 263 will effect translation of rack 277 thereby driving spur gear 269 fixed to shaft 273. Since there is no input drive to effect pivoting of the first phalanx link 259, rack 279 can not be induced to translate by walking around spur gear 265. Therefore since spur gear 271 is fixed to common shaft 273, spur gear 271 will be constrained to walk along rack 279 and cause translation of common shaft 273 in its journal slot mount 275. Rack 291 will in turn translate driving spur gear 287 fixed to shaft 285. The second phalanx 289 fixed to shaft 285 will therefore pivot.

Combined thumb movements can be effectuated by driving two of the three input spur gears 25, 27 and 49 or by driving all three of these input spur gears simultaneously.

With reference to FIG. 1 of the drawings input spur gear 15 meshes With sector gear 295 integral to the metacarpal frame structure 55. Spur gear 297, fixed to Wrist frame 5, meshes with spur gear 299 fixed to shaft301 that is freely mounted in the metacarpal frame struc ture 55. Also fixed to shaft 301 are spur gears 303, 305, 307, 309, 311, 313, 315 and 317 which are in alignment with respective input spur gears 7, 9, 11, 13, 17, 19, 21 and 23. Operatively engaged with each of the spur gears 303, 305, 307, 309, 311, 313, 315 and 317 are respective racks 319, 321, 323, 325, 327, 329, 331 and 333. Spacer elements 335, 337, 339, 341, 343, 345, 347, 349 and 351 are showndisposed between the spur gears 303, 305, 307, 309, 311, 313, 315 and 317.

Further description of racks 323 and 325 is with reference to the ring finger. It should be discerned and I appreciated that the structure of racks 319, 321, 327,

329, 331 and 333 and their structural cooperations and associations with respective spur gears 303, 305, 311, 313, 315 and 317 are similar to the description afforded spur gears 307 and 309.

Racks 325 and 323 are held in their operative engagement with spur gears 309 and 61, and spur gears 307 and 83, respectively, by rack guide pins 353 carried by the spacer elements 341 and 339.

Wrist pivot without finger movement is effectuated when input spur gear 15 transmits drive to sector gear 295 of the metacarpal frame structure 55, and thereby pivoting the metacarpal frame structure 55 about the Wrist pivot shaft 53. Since no input drive is being transmitted to any of the input spur gears 7, 9, 11, 13, 17, 19, 21 and 23, these enumerated input spur gears will remain stationary as will the spur gears 51 that are in mesh with these enumerated input spur gears. Upon pivoting of the metacarpal frame structure 55 about the wrist pivot shaft 53, the racks 59 will translate upon walking around spur gears 51 transmitting drive in one direction to spur gears 61 and 83 and all other spur gears that are arranged and disposed similar to spur gears 61 and 83 in the little finger, middle finger and forefinger.

Spur gear 297 is fixed to wrist frame and wrist pivot shaft 53 is fixed to the metacarpal frame structure 55. Upon pivoting of the metacarpal frame structure 55, spur gear 299 will walk around spur gear 297 and spur gears 303, 305, 307, 309, 311, 313, 315 and 317 that are fixed to shaft 301 will be driven. These spur gears 303, 305, 307, 309, 311, 313, 315 and 317 are operatively engaged with and translate racks 319, 321, 323, 325, 327, 329, 331 and 333, respectively.

The particular functional attribute of racks 323 and 325 in conjunction with spur gears 83 and 61 of the ring finger is similar of course to the functional attributes of racks 319 and 321, 327 and 329, 331, and 333, of the little finger, middle finger and forefinger, respectively. Racks 323 and 325 in their translatory movements will move in a direction opposite but equal in magnitude to the translation of the two cooperatively associated racks 59 thereby preventing gears 83 and 61 from translating. The result will be that the shafts 85 and 63 will not translate within their journal slots 87 and 65, and hence the cooperatively and operatively associated racks 91 and 75 will not translate thereby preventing respectively, any finger curl and finger pivot from taking place. It should further be discerned and appreciated that finger curl and finger pivot will not take place in the little finger, middle finger and forefinger.

Wrist pivot without thumb metacarpal movement relative to the inoperative position of the thumb metacarpal is eifectuat-ed with a concomitant compensatory action of the spur gear differential when input spur gear transmits drive to sector gear 295 of the metacarpal frame structure 55 thereby driving wrist pivot shaft 53. Input spur gear 49 is of course stationary with no input drive being transmitted to it. Spur gear 197 fixed to wrist pivot shaft 53 is driven along with spur gears 199, 179 and 177. Spur gears 1'77 and 173 are fixed to common shaft 175 and drive is transmitted to spur gear 171. Rack 181 is translated which effects rotation to spur gear 183 and the bevel gear 185 fixed therewith. Compensatory drive of first metacarpal link 201 is effected through its driven bevel sector gear 203, thereby preventing first metacarpal movement.

Wrist pivot without thumb first phalanx pivot and thumb second phalanx pivot (thumb curl) is eifectuated, with input spur gears and 27 stationary, when input spur gear 15 transmits drive to sector gear 295 of the metacarpal frame structure 55 thereby driving wrist pivot shaft 53 and pivoting block 193 fixed to wrist pivot shaft 53. Bevel gear 198, fixed to shaft 195, walks around bevel sector gear 196 driving shaft 195 and spur gears 213 and 219 fixed to shaft 195. Racks 229 and 237 operatively engaged with spur gears 213 and 219, respectively, are translated in one direction. With no input drive being transmitted to input spur gears 25 and 27, spur gears 205, and 209, respectively, will remain stationary. Bevel sector gear 207, fixed to spur gear 205, meshes with bevel gear 217 fixed to spur gear 215; and bevel sector gear 211, fixed to spur gear 209, meshes with bevel gear 223 fixed to spur gear 221. Bevel gear 217 walks around bevel sector gear 207 carrying spur gear 215 and translating offset rack 231 in a direction opposite to the direction that rack 229 is translating. Bevel gear 223 walks around bevel sector gear 211 carrying spur gear 221 and translating rack 239 in a direction opposite to the direction that offset rack 237 is translating. Hence translating shafts 227 and 235, to which respective spur gears 225 and 233 are fixed, are not translated.

Rack 253 carried by shaft 227 does not translate to induce drive to operatively engaged spur gears 249, 263 and rack 277. It should be discerned that with no first phalanx movement, gear 265 can not induce translatory motion to rack 27 9 and eifect rotation to gear 271. Since racks 277 and 279 do not translate, shaft 273 carrying rack 291 can not translate to cause rotation to spur gear 287 and shaft 285 fixed to it. Second phalanx link 289 being fixed to shaft 285 will therefore remain stationary thus precluding second phalanx pivot.

It can also be discerned that rack 255, carried by nontranslated shaft 235 can not drive gear 251 to effect rotation to sector gear 267 fixed to first phalanx link 259. Hence with no rotation of sector gear 267 the first phalanx link 259 remains stationary and first phalanx pivot can not occur about shaft 261.

By referring to the drawings it can be discerned that the utilized drive combinations are technically known as multi-input type analog computer mechanisms. Said multi-input type analog computer mechanisms can be further broken down into standard species. This invention features the differential specie of which the spur gear and the rack and gear types are exclusively used. The said multi-input type analog computer mechanisms exist in the following combinations:

Combination of gear 51, rack 59, gear 61, rack 325 and gear 309.

Combination of gear 51, rack 59, gear 83, rack 323 and gear 307.

Combination of gear 123, rack 125, gear 127, gear 131, rack 129 and gear 119.

Combination of gear 213, rack 229, gear 225, rack 231 and gear 215.

Combination of gear 219, rack 237, gear 233, rack 239 and gear 221.

Combination of gear 263, rack 277, gear 269, gear 271, rack 279 and gear 265.

Combination of gear 199, gear 179, gear 177, gear 173 and gear 171.

Having thusly described my invention, I claim:

1. A mechanical hand comprising, in combination, a carpus, a metacarpus pivotally connected to said carpus, a thumb and a finger pivoted with respect to said metacarpus, drivably connected multi-input type analog computer mechanisms functionally associated with said carpus, metacarpus, thumb and finger, and input drive means operatively associated with said computer mechanisms to effectuate hand movements.

2. A mechanical hand comprising, in combination, a carpus, a metacarpus pivotally connect-ed to said carpus, a thumb and a finger pivoted with respect to said metacarpus, drivably connected differential mechanisms functionally associated with said carpus, metacarpus, thumb and finger, and input drive means operatively associated with said differential mechanisms to effectuate hand movements.

3. A mechanical hand comprising, in combination, a carpus, a metacarpus pivotally connected to the said carpus, a thumb and a finger pivoted with respect to said metacarpus, a drivably connected spur gear differential mechanism functionally associated with the carpus and thumb, drivably connected rack and gear differential mechanisms functionally associated with said carpus, metacarpus, thumb and finger, and input drive means operatively associated with said differential mechanisms to effectuate hand movements.

4. A mechanical hand comprising, in combination, a carpus, a metacarpus pivotally connected to said carpus, a thumb and four fingers pivoted with respect to said metacarpus, drivably connected multi-input type analog computer mechanisms functionally associated with said carpus, metacarpus, thumb and fingers, and input drive means operatively associated with said analog computer mechanisms to effectuate hand movements.

5. A mechanical hand comprising, in combination, a carpus, a metacarpus pivoted to said carpus, a proximal phalanx member pivoted to said metacarpus, a middle phalanx member pivoted on said proximal phalanx member, a distal phalanx member pivoted on said middle phalanx member, a first phalanx member pivoted on said metacarpus, a second phalanx member pivoted on said first phalanx member, drivably connected multi-input type analog computer mechanisms functionally associated with said carpus, metacarpus, proximal phalanx, middle phalanx, distal phalanx, first phalanx, and second phalanx members, and input drive means operatively associated with said analog computer mechanisms to effectuate hand movements.

6. A mechanical hand comprising, in combination, a carpus, a metacarpus pivoted to said carpus, a plurality of proximal phalanx mem'bers pivoted to said metacarpus, a plurality of middle phalanx members pivoted on said proximal phalanx members, a plurality of distal phalanx members pivoted on said middle phalanx members, a first phalanx member pivoted to said metacarpus, a second phalanx member pivoted on said first phalanx member, drivably connected multi-input type analog computer mechanisms functionally associated with said carpus, metacarpus, proximal phalanxes, middle phalanxes, distal 10 phalanxes, first phalanx, and second phalanx members, and input drive means operatively associated with said analog computer mechanisms to efiectuate hand movements.

References Cited UNITED STATES PATENTS 1,380,835 6/1921 Pecorella et a1. 312.6 X 1,507,682 9/1924 Pecorella et al 3-l2.'7 X 2,580,987 1/1952 Alderson 3-126 X OTHER REFERENCES RICHARD A. GAUDET, Primary Examiner. ROBERT E. MORGAN, Examiner.

5 R. L. F-RINKS, Assistant Examiner. 

1. A MECHANICAL HAND COMPRISING, IN COMBINATION, A CARPUS, A METACARPUS PIVOTALLY CONNECTED TO SAID CARPUS, A THUMB AND A FINGER PIVOTED WITH RESPECT TO SAID METACARPUS, DRIVABLY CONNECTED "MULTI-INPUT TYPE ANALOG COMPUTER MECHANISMS" FUNCTIONALLY ASSOCIATED WITH SAID CAR- 